Assets Management

Phalcon\Assets is a component that allows you to manage static resources such as CSS stylesheets or JavaScript libraries in a web application.

Phalcon\Assets\Manager is available in the services container, so you can add resources from any part of the application where the container is available.

Adding Resources

Assets supports two built-in resources: CSS and JavaScripts. You can create other resources if you need. The assets manager internally stores two default collections of resources - one for JavaScript and another for CSS.

You can easily add resources to these collections like follows:

<?phpusePhalcon\Mvc\Controller;classIndexControllerextendsController{publicfunctionindex(){// Add some local CSS resources$this->assets->addCss('css/style.css');$this->assets->addCss('css/index.css');// And some local JavaScript resources$this->assets->addJs('js/jquery.js');$this->assets->addJs('js/bootstrap.min.js');}}

For better page load performance, it is recommended to place JavaScript at the end of the HTML instead of in the <head>.

Local/Remote resources

Local resources are those who are provided by the same application and they’re located in the document root of the application. URLs in local resources are generated by the url service, usually Phalcon\Mvc\Url.

Remote resources are those such as common libraries like jQuery, Bootstrap, etc. that are provided by a CDN.

The second parameter of addCss() and addJs() says whether the resource is local or not (true is local, false is remote). By default, the assets manager will assume the resource is local:

<?phppublicfunctionindexAction(){// Add some remote CSS resources$this->assets->addCss('//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.2/css/bootstrap-combined.min.css',false);// Then add some local CSS resources$this->assets->addCss('css/style.css',true);$this->assets->addCss('css/extra.css');}

Collections

Collections group resources of the same type. The assets manager implicitly creates two collections: css and js. You can create additional collections to group specific resources to make it easier to place those resources in the views:

<?php// Javascripts in the header$headerCollection=$this->assets->collection('header');$headerCollection->addJs('js/jquery.js');$headerCollection->addJs('js/bootstrap.min.js');// Javascripts in the footer$footerCollection=$this->assets->collection('footer');$footerCollection->addJs('js/jquery.js');$footerCollection->addJs('js/bootstrap.min.js');

Minification/Filtering

Phalcon\Assets provides built-in minification of JavaScript and CSS resources. You can create a collection of resources instructing the Assets Manager which ones must be filtered and which ones must be left as they are. In addition to the above, Jsmin by Douglas Crockford is part of the core extension offering minification of JavaScript files for maximum performance. In the CSS land, CSSMin by Ryan Day is also available to minify CSS files.

The following example shows how to minify a collection of resources:

<?php$manager// These JavaScripts are located in the page's bottom->collection('jsFooter')// The name of the final output->setTargetPath('final.js')// The script tag is generated with this URI->setTargetUri('production/final.js')// This is a remote resource that does not need filtering->addJs('code.jquery.com/jquery-1.10.0.min.js',false,false)// These are local resources that must be filtered->addJs('common-functions.js')->addJs('page-functions.js')// Join all the resources in a single file->join(true)// Use the built-in Jsmin filter->addFilter(newPhalcon\Assets\Filters\Jsmin())// Use a custom filter->addFilter(newMyApp\Assets\Filters\LicenseStamper());

A collection can contain JavaScript or CSS resources but not both. Some resources may be remote, that is, they’re obtained by HTTP from a remote source for further filtering. It is recommended to convert the external resources to local for better performance.

As seen above, the addJs() method is used to add resources to the collection, the second parameter indicates whether the resource is external or not and the third parameter indicates whether the resource should be filtered or left as is:

<?php// These Javascripts are located in the page's bottom$jsFooterCollection=$manager->collection('jsFooter');// This a remote resource that does not need filtering$jsFooterCollection->addJs('code.jquery.com/jquery-1.10.0.min.js',false,false);// These are local resources that must be filtered$jsFooterCollection->addJs('common-functions.js');$jsFooterCollection->addJs('page-functions.js');

Filters are registered in the collection, multiple filters are allowed, content in resources are filtered in the same order as filters were registered:

<?php// Use the built-in Jsmin filter$jsFooterCollection->addFilter(newPhalcon\Assets\Filters\Jsmin());// Use a custom filter$jsFooterCollection->addFilter(newMyApp\Assets\Filters\LicenseStamper());

Note that both built-in and custom filters can be transparently applied to collections. The last step is to decide if all the resources in the collection must be joined into a single file or serve each of them individually. To tell the collection that all resources must be joined you can use the join() method.

If resources are going to be joined, we need also to define which file will be used to store the resources and which URI will be used to show it. These settings are set up with setTargetPath() and setTargetUri():

<?php$jsFooterCollection->join(true);// The name of the final file path$jsFooterCollection->setTargetPath('public/production/final.js');// The script HTML tag is generated with this URI$jsFooterCollection->setTargetUri('production/final.js');

Built-In Filters

Phalcon provides 2 built-in filters to minify both JavaScript and CSS, their C-backend provide the minimum overhead to perform this task:

<?php// Get some CSS collection$css=$this->assets->get('head');// Add/Enable the YUI compressor filter in the collection$css->addFilter(newCssYUICompressor(['java-bin'=>'/usr/local/bin/java','yui'=>'/some/path/yuicompressor-x.y.z.jar','extra-options'=>'--charset utf8',]));

Custom Output

The outputJs() and outputCss() methods are available to generate the necessary HTML code according to each type of resources. You can override this method or print the resources manually in the following way:

Improving performance

There are many ways to optimize the processing resources. We’ll describe a simple method below which allows to handle resourses directly through web server to optimize the response time.

First we need to set up the Assets Manager. We’ll use base controller, but you can use the service provider or any other place:

<?phpnamespaceApp\Controllers;usePhalcon\Mvc\Controller;usePhalcon\Assets\Filters\Jsmin;/**
* App\Controllers\ControllerBase
*
* This is the base controller for all controllers in the application.
*/classControllerBaseextendsController{publicfunctiononConstruct(){$this->assets->useImplicitOutput(false)->collection('global')->addJs('https://code.jquery.com/jquery-3.2.1.js',false,true)->addFilter(newJsmin());}}

Then we have to configure the routing:

<?php/*
* Define custom routes.
* This file gets included in the router service definition.
*/$router=newPhalcon\Mvc\Router();$router->addGet('/assets/(css|js)/([\w.-]+)\.(css|js)',['controller'=>'assets','action'=>'serve','type'=>1,'collection'=>2,'extension'=>3,]);// Other routes...

If precompiled resources exist in the file system they must be served directly by web server. So to get the benefit of static resources we have to update our server configuration. We will use an example configuration for Nginx. For Apache it will be a little different:

location~^/assets/{expires1y;add_headerCache-Controlpublic;add_headerETag"";# If the file exists as a static file serve it directly without
# running all the other rewrite tests on it
try_files$uri$uri/@phalcon;}location/{try_files$uri$uri/@phalcon;}location@phalcon{rewrite^(.*)$ /index.php?_url=$1;}# Other configuration

We need to create assets/js and assets/css directories in the document root of the application (eg. public).

Every time when the user requests resources using address of type /assets/js/global.js the request will be redirected to AssetsController in case this file is absent in the filesystem. Otherwise the resource will be handled by the web server.

It isn’t the best example. However, it reflects the main idea: the reasonable configuration of a web server with an application can help optimize response time multifold.